Steam iron additive composition



United States Patent Ofilice 3,505,237 Patented Apr. 7, 1970 3,505,237STEAM IRON ADDITIV'E COMPOSITION Roger C. Steinhauer, Park Forest, Ill.,assignor to Armour and Company, Chicago, 11]., a corporation of DelawareNo Drawing. Filed Mar. 6, 1967, Ser. No. 620,655 Int. Cl. C23f 14/02;D06f 75/14 US. Cl. 252-180 9 Claims ABSTRACT OF THE DISCLOSURE A steampromoting composition comprising as essential active ingredients apolyethylene glycol having a molecular weight of from 120 to 1000 and asiloxanepolyoxyalkylene block copolymer having molecular weight of from400 to 600.

BACKGROUND OF THE INVENTION My invention pertains to an aqueouspolyethylene glycol and silicone fluid composition which may be added tothe water in the reservoir of steam producing apparatus such as steamirons to enhance steam production and to change the character of hardmineral scales within such apparatus.

Steam irons generally comprise an electrically heat controlled soleplate and a reservoir for water which is heated in the iron and releasedtherefrom as steam through holes in the sole plate. The water is eitherheated to steam in the reservoir; or, in the more popular style of steamiron commonly called the flash boiler type, the water is released fromthe reservoir through an actuated needle valve in a drop-wise fashion,and when each drop of water comes into contact with the hot sole plateit flashes to steam and escapes through the holes in the sole plate.

Problems encountered by the consumer in the use of steam irons includesputtering, leaking and dripping of hot water that has not flashed tosteam, insufficient production of steam due to bubble or foam formationof the water and other factors, and clogging of the needle valve ventdue to hard Water scale build-up. Hard water, containing calcium,magnesium and other minerals, can cause very serious scale problems. Itsuse in steam irons shortens the life of the iron considerably andgenerally steam iron manufacturers warn against using it in theirproducts. The scale that is formed from hard Water deposits is very hardand brittle; once it has formed, it is most difficult to remove.

Polyethylene glycol esters prepared from polyethylene glycols havingmolecular weights of from 400 to 1000 have been used in mixture withhydrocarbon soluble organopolysiloxane for defoaming latex paints andadhesive materials (United States Patent 2,843,551), Also,polyoxyalkylene glycols having a molecular weight of from 1000 to 11,500have been used in a method for inhibiting foam formation in boilerwater, under super-atmospheric temperature and pressure conditions, witha high concentration of total dissolved solids in the water (UnitedStates Patent 2,846,404).

SUMMARY OF THE INVENTION My invention relates to a new composition ofmatter, said composition possessing excellent utility for increasingsteam production in steam promoting apparatus. More particularly itrelates to a composition which may be added to the water in a steam ironfor purposes of promoting steam production and of changing the characterof hard water scale build-up.

Therefore, it is an object of this invention to provide a newcomposition of matter, said composition having particular utility insteam producing apparatus. It is an object of this invention to providea composition to enhance production of steam from water, and inparticular, the water in steam irons. Another object of this inventionis to produce extra steam in a steam iron Without causing spitting ordripping. A further object of this invention is to inhibit needle valveclogging when hard water is used in steam irons by changing the natureof the scale build-up from a hard brittle thick coating to a soft fuzzythinner deposit which is easier to remove. Still another object of thisinvention is to make ironing easier by imparting a lubricating film tothe fabric and reducing static electricity charge build-up on thefabric. It is still another object of this invention to impart a supple,wrinkle resistant finish to the ironed fabric. A further object of thisinvention is to impart a fresh clean odor to the ironed fabric. Otherobjects and advantages and a fuller understanding of my invention willbecome more apparent from the ensuing description and examples.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a specific embodiment, myinvention may be exemplified by the composition to be added to the waterin a steam iron comprising, in combination, a stable oil in wateremulsion of (1) a polyethylene glycol having a molecular weight of fromabout to 1000, (2) a s'iloxane -polyoxyethylene block copolymer having amolecular weight of from about 400 to 600, (3) an aqueous formaldehydesolution, (4) a relatively nonvolatile perfume, (5) a relativelynonvolatile dye and (6) distilled or demineralized water. Thepolyethylene glycol and the siloxane-polyoxyethylene block copolymer areessential active ingredients of my invention; the other components maybe added for a preferred composition accomplishing the above and otherobjects. About one part of the composition by volume may be added toabout nine parts by volume of either tap Water, demineralized ordistilled water for use in steam irons.

The novel composition of the present invention contains a polyethyleneglycol as one essential component. The polyethylene glycols suitable foruse in the practice of this invention are characterized by a pluralityof ether linkages and two terminal hydroxyl groups, and have a molecularweight of from about 120 to 1000. I prefer to use polyethylene glycolshaving a molecular weight of from about to about 600. Especiallydesirable polyethylene glycols are heat stable, less hygroscopic andafford better lubricity than simple glycols and glycerine, have aboiling point of approximately 280" to 310 F., and a molecular weight offrom about to about 210. The amount of the polyethylene glycol in thecomposition may vary over wide ranges depending on the use ratio of thecomposition in the water to be steamed. A preferred concentration isfrom about 7% to about 10% by volume in a composition to be used in asteam iron at a rate of one part of composition by volume to nine partsby volume of Water.

The composition of the present invention contains as a second essentialingredient a siloxane-polyoxyalkylene block copolymer, or siliconefluid. Silicone fluids suitable for use in the practice of thisinvention are organosilicone fluids with surface active properties,having a molecular weight of from 400 to 600, which embody theproperties of both organic and silicone oils and impart good lubricationand anti-wear properties. Silicone fluids having a molecular weight offrom about 500 to about 550 are preferred. The deforming properties ofthe silicone fluids useful in my invention tend to inhibit bubbleformation thereby enhancing steam liberation. Concentration of theuseful silicone fluids in my composition may vary from 0.01% to 10%,again depending upon use ratio of the composition in the water. Apreferred concentration is from about 0.05% to about 1.5% concentrationin a :omposition to be used in a steam iron at a rate of one part byvolume of composition to nine parts by volume of water.

The proportions of the two essential ingredients are not critical.However, I generally prefer proportions by volume of the glycol to thesilicone fluid ranging from about 1:1 to about 30:1 to accomplish theobjects of my invention.

The third component of my composition exemplified in the above specificembodiment is an aqueous solution of formaldehyde. Such solution ispreferably at 36% active formalin solution but may be any other likeformaldehyde yielding material. Its role in the composition is to serveas a preservative. It is not essential that formaldehyde or likesubstance be present in the composition, but its presence is desirabledue to the fact that aqueous solutions of polyethylene glycol serve as agood medium for the growth of mold. Therefore, it is useful toincorporate in the composition a concentration of from about 0.05% to1.0% of a 36% active formalin solution. A preferred concentration isfrom 0.1% to 0.2%.

The remaining components of the composition exemplified in the specificembodiment hereinabove are a perfume and a dye. These are optionalcomponents, and if they are used at all it is preferred that they benon-volatile and that their amounts be kept to an absolute minimum.

The concentration of my composition in the water to be steamed may varyover a wide range. I may use the composition as is or in a dilutionratio. A dilution ratio ranging from about 1:1 to about 100:1 isgenerally desirable when the composition is used in steam irons. About7:1 to about 10:1 is preferred. The concentration is not critical andconcentrations outside these ranges may be used, but without substantialenhanced effect.

Using my com-position and hard water in steam irons does notsubstantially decrease scale build-up. However, the character of thescale is changed to a softer, looser, granular residue which does notcause needle valve clogging as readily as hard water alone. Apparently,these soft granules are to an extent flushed off by water released fromthe reservoir, thereby extending the useful life of the iron.

In order to more fully describe the nature of my composition and themanner in which it may be used, the following illustrative specificexamples are provided.

EXAMPLE I Any compound added to the water in a steam iron to increasesteam production must, in addition, not cause clogging of the needlevalve vent or the steam vents. Nor may such a compound leave appreciableresidual deposits when dilute aqueous solutions containing the com-poundare evaporated from a hot surface. In accord with these criteria, anumber of polyethylene glycols and silicone fluids were evaluated by thefollowing procedure:

A thermostatically controlled hot plate was positioned on the base of aring stand and two disposable aluminum weighing dishes were placed onthe hot plate. Two 50 ml. burets were clamped to the ring stand so thateach was positioned over an aluminum dish, and the burets were,

charged with ml. of an aqueous solution of the test compound in oneburet and 25 ml. of water in the other. In one phase of this evaluationdistilled water was used in order to determine the residual propertiesof the compounds in the absence of hard water salts. In the other phaseof this evaluation, tap water having a hardness of 135 ppm. was used inthe solution and compared to a tap water only control. The solutionscontained an active concentration of 0.5% of the compounds beingevaluated. The hot plate was adjusted to maintain the aluminum dishes ata temperature of 350 F. and the contents were allowed to drip into thehot aluminum dishes at a rate that would prevent pooling of the liquid.During this operation the steam producing properties of the solutionswere visually observed and recorded. After the burets had emptied andall volatiles had evaporated from the dishes, the dishes were weighed.The amount of any residue was recorded in grams and the percent ofnon-volatile residue for the solutions were compared to the watercontrols. Steaming properties and residual deposit characteristics forthe compounds evaluated in distilled water are set forth in Table I.TableII shows the corresponding data for tap water.

From Table I it may be seen that the polyethylene glycols tested ingeneral increase steam and leave little or no residual deposits. Most ofthe silicones evaluated leave appreciable deposits and have no effect onsteam production. Combining the silicone with the polyethylene glycolresults in a composition that increases steam production without leavinga substantial residue. In tap water (Table II) the polyethylene glycolsalone produced more steam but had little effect on hard water scalebuild-up. Incorporation of Silicone L520 with the lower molecular weightpolyethylene glycol did change the nature of the hard water deposits.

TABLE 1'.

[0.5% solutions in distilled water] 0.5% Solution Residue twt.) Addltive Steam (gms.) Percent Properties None (control) 25 0 Carhowax200... Increased.-.. 25 0. 23 Dry. Carbowax 600 do 25 0. 47 Dry, sticky.Carbowax 1000.. 25 0.77 81., oily. Carbowax (i000 do 25 1.03 Oily.Silicone L-7l3. No effect 25 0. Waxy. Silicone L520 Slight increase.25 1. 20 Do. Silicone L522 No effect 25 1. 27 Charred. Silicone L527 d25 1.31 Do. Silicone L530 do 25 1 29 Do. Silicone L5310 do 25 1. 14Waxy. Silicone XFI-lOOl do 25 1. 43 Charred. Silicone XF-1007 do 25 1.56 Do. 3 to 1 Silicone L- Increased. 25 0. 71 Oily.

520 and Garbowax 600. 9 to 1 Carbowax do 25 0. 49 Dry.

200 and Silicone L520.

TABLE II [0.5% solutions in tap Water p.p.m. hardness)] 0.5% SolutionResidue (\vt.) Additive Steam (gms.) Percent Properties None (control)25 0 Carbowax 200" Increased... 25 Dry. Carbowax 600... do 2b 0. 44 Dry,sticky. Carbowax 6000 do 25 1.03 Oi and salt ep. Silicone L520 No eiTect25 1 12 Waxy. 3 to 1 Silicone L520 Increased 25 0. 71 Charred andGarbowax 600. film. 9 to 1 Oarbowax 200 .-..rlo 25 0. 49 No charring.

and Silicone L520.

EXAMPLE II Steam production rates were determined for my com position intap water and in distilled by the following procedure. The waterreservoir of a flash boiler type of steam iron was filled with distilledwater, the filled iron was weighed on a balance scale and the weightrecorded. With the iron still resting upon the balance, steaming wasstarted and the weight loss was periodically recorded until all waterhad steamed out. This was repeated for several runs and the averageweight loss in grams per minute (g./m.) was recorded. The procedure wasrepeated adding, to 9 parts of distilled water, 1 part of the followingcomposition:

Percent Carbowax 200 8.9 Silicone L520 1.0 Formalin (36%) 0.15 Perfume0.10 Distilled water 89.85

TABLE III Steaming Rate Distilled Water aging upon it. At that time,steam rates were again determined in distilled water using the procedureof Example II. The data for 3 runs is set forth in Table IV.

moting apparatus comprising from 0.05% to 50% concentration of apolyethylene glycol having a molecular weight of from about 120 to 1000,and from 0.01%

to of a siloxane-polyoxyethylene block copolymer having a molecularweight of from 400 to 600 and the balance of the composition beingwater.

2. The composition of claim 1 in which the molecular weight of saidglycol is from about 175 to about 600.

3. The composition of claim 1 in which the molecular Weight of saidglycol is from about 190 to about 210.

4. The composition of claim 1 in which the molecular weight of saidcopolymer is from about 500 to about 550.

5. The composition of claim 1 in which the concentration of said glycolis from about 7% to about 10%.

6. The composition of claim 1 in which the contration of said copolymeris from about 0.05 to about 1.5%.

7. The composition of claim 1 in which the composition includes from0.05% to 1% of a 36 active formalin solution.

TAB LE IV.--STEAM P ROD UC TION Distilled Water Only, Grams Lost (min).

Distilled Water With Aged Sample,

Grams Lost (min) Minutes 4 s 12 16 20 24 2s 32 36 Minutes 4 s 12 16 20Initial Weight: Initial weight:

02 94 118 130 153 170 105 217 Avg 54 106 154 102 21s EXAMPLE IV 8. Thecomposition of claim 1 added to said water at It has been found thatflash-boiler" style steam irons clog at the needle valve seat aftercontinuously steaming approximately 3 to 4 gallons of tap Water having ahardness of 37 grains per gallon.

Using 3.4 cups of the composition of Example II per gallon of tap waterhaving a hardness of 37 grains, I evaluated the composition for thelength of time it could be continuously steamed from this style steamiron before clogging the iron at the needle valve seat. The water wassiphoned continuously into the iron reservoir and allowed to steam untilthe iron clogged. I found that the iron did not clog until after 6.4gallons had been steamed. Repeating the evaluation using the samecomposition addition rate and the same composition but without theperfume component, 7.1 gallons of this water steamed through the ironbefore it clogged.

I claim:

1. A steam promoting stable oil in water emulsion composition to beadded to the water of a steam proa dilution ratio ranging from about 1:1to about 100:1.

9. The composition of claim 1 added to said water at a dilution ratioranging from about 7:1 to about 10:1.

References Cited UNITED STATES PATENTS 2,467,177 4/1949 Zimmer 252-3212,843,551 7/1958 Leonard et a1. 252321 2,846,404 8/ 1958 Johnson 252-3212,990,377 6/1961 May 252--312 3,359,212 12/1967 Bailey 2523 12 LEON D.ROSDOL, Primary Examiner I. GLUCK, Assistant Examiner

